Roots & Shoots Blog

On Thanksgiving we Americans remember our many blessings. High among these is our world with a climate that has made possible the evolution of humans like us with brains that can understand and alter both ourselves and the environment that sustains us. I start with that because we have no responsibility for designing either our brains or our environment.

Our home, the earth, is four billion years old. Beings like us appeared about 120 thousand years ago when the earth had already existed for about 97 percent of its life. Scientists have searched for clues as to how we reached this point. Evidence suggests that about seventy thousand years ago a giant volcano blew up on Sumatra putting so much debris in the air that the sunshine reaching the earth was diminished for three years. As a result, many species perished. A small number of humans survived on the East coast of Africa by eating shell fish surviving in the warm currents from the Pacific Ocean. This genetic bottleneck probably explains why we humans are more alike than expected through natural evolution.

In the late 19th and early 20th centuries the world’s human population began explosive growth, going from about half a billion to 7 billion. Knowledge including medical and agricultural sciences expanded; infant mortality fell and life expectancy lengthened. The population continues to grow and is expected to add another 3 billion in the next 30 years.

With this increase in population we have used more land, water and fertilizer to feed more and more people and burned more fossil fuels for heat, cooling and transportation. The burning of fossil fuel adds to the carbon dioxide in ambient air, resulting in global warming. Thus, we live in an unstable and changing world that makes more difficult both science and agricultural planning. We humans need to change and adapt as best we can to climate variability.

I believe that Danforth Center scientists will prepare the human race better to understand and adapt to our changing world. Few undertakings can be more important.

Thank you for joining with us. May our work be remembered and blessed in future Thanksgivings.